U.S. patent application number 15/301595 was filed with the patent office on 2017-01-19 for treatment of glass surfaces for improved adhesion.
The applicant listed for this patent is Corning Incorporated. Invention is credited to Rebecca Lee DeRosa, Jiangwei Feng, James Patrick Hamilton, James Robert Matthews, Yasuyuki Mizushima, Hisanori Nakanishi, Wanda Janina Walczak.
Application Number | 20170015583 15/301595 |
Document ID | / |
Family ID | 54241244 |
Filed Date | 2017-01-19 |
United States Patent
Application |
20170015583 |
Kind Code |
A1 |
DeRosa; Rebecca Lee ; et
al. |
January 19, 2017 |
TREATMENT OF GLASS SURFACES FOR IMPROVED ADHESION
Abstract
A patterned article and a method of making the patterned
article. The patterned article comprises a glass substrate and
black matrix segments. The black matrix segments are in the form of
a pattern and at least one of the segments has a line width of 8
.mu.m or less. The article also comprises an adhesion agent
positioned between the glass substrate and the black matrix
segments. The adhesion agent provides at least one of: a total
surface energy of 65 mN/m or less and at least a 30% reduction in
surface polarity compared to a control untreated glass surface as
determined by H.sub.2O and diiodomethane contact angle and
application of the Wu model.
Inventors: |
DeRosa; Rebecca Lee;
(Painted Post, NY) ; Feng; Jiangwei; (Newtown,
PA) ; Hamilton; James Patrick; (Horseheads, NY)
; Matthews; James Robert; (Painted Post, NY) ;
Mizushima; Yasuyuki; (Kakegawa, Shizuoka, JP) ;
Nakanishi; Hisanori; (Hamamatsu City, JP) ; Walczak;
Wanda Janina; (Big Flats, NY) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Corning Incorporated |
Corning |
NY |
US |
|
|
Family ID: |
54241244 |
Appl. No.: |
15/301595 |
Filed: |
April 1, 2015 |
PCT Filed: |
April 1, 2015 |
PCT NO: |
PCT/US2015/023774 |
371 Date: |
October 3, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61975160 |
Apr 4, 2014 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C03C 27/00 20130101;
G02F 1/133516 20130101; C03C 2218/116 20130101; C03C 2218/151
20130101; G02F 1/133514 20130101; C03C 17/3405 20130101; G02F
2001/133302 20130101; G02F 1/133512 20130101 |
International
Class: |
C03C 17/34 20060101
C03C017/34; G02F 1/1335 20060101 G02F001/1335 |
Claims
1. A patterned article comprising: a glass substrate; black matrix
segments; wherein the black matrix segments are in the form of a
pattern and at least one of the segments has a line width of less
than 8 .mu.m; and an adhesion agent positioned between the glass
substrate and the black matrix segments, wherein the adhesion agent
provides at least one of: a total surface energy of the glass
substrate of 65 mN/m or less; and at least a 30% reduction in
surface polarity compared to a control untreated glass surface, as
determined by water and diiodomethane contact angle
measurements.
2. The article of claim 1 wherein the adhesion agent provides at
least a 30% reduction in the polar component of the overall surface
tension of the glass substrate relative to a non-treated control
substrate.
3. The article of claim 1 wherein the black matrix segments in the
first direction, or the black matrix segments in the second
direction, have a line width in the range of 2 .mu.m to 4
.mu.m.
4. The article of claim 1 wherein the adhesion agent is a fatty
chain functional organic selected from the group consisting of
alkyl amine, alkyl alcohol, alkyl epoxy, alkyl acid, and alkyl
silane.
5. The article of claim 1 wherein the adhesion agent is a
substituted alkyl silane.
6. The article of claim 5 wherein the substituted alkyl silane
includes a functional group selected from the group consisting of a
quaternary nitrogen, an ether and a thioether, and a pendent
(C.sub.6-C.sub.30)alkyl that extends from the functional group.
7. The article of claim 5 wherein the substituted alkyl silane
includes a quaternary nitrogen and a pendent
(C.sub.10-C.sub.24)alkyl.
8. The article of claim 1 that exhibits an increase in delamination
time of at least 5 seconds of a test segment with a line width of 5
.mu.m following contact with a 0.24 wt % aqueous potassium
hydroxide solution, relative to a control article.
9. The article of claim 8 that exhibits an increase in delamination
time of at least 5 seconds of a test segment with a line width of 5
.mu.m following contact with a 1.0 wt % aqueous sodium carbonate
solution, relative to a control article.
10. A flat panel display comprising the patterned article of claim
1.
11. The flat panel display of claim 10 wherein the patterned
article is a color filter array.
12. A method of improving the adhesion of black matrix on a glass
substrate, the method comprising: providing a glass substrate;
treating a surface of the glass substrate with an adhesion agent,
wherein the adhesion agent provides a total surface energy of 65
mN/m or less as determined by water and diiodomethane contact angle
measurements; applying a black matrix material to the surface of
the glass substrate that is treated with the adhesion agent; and
creating a pattern within the black matrix material, wherein the
pattern includes black matrix segments and at least one of the
black matrix segments has a line width less than 8 .mu.m.
13. The method of claim 12, wherein after treating the surface of
the glass substrate with the adhesion agent and immediately prior
to applying the black matrix material to the surface of the glass
substrate that is treated with the adhesion agent, the adhesion
agent remains on the glass surface in sufficient quantity to
provide at least one of: a total surface energy of the glass
substrate of 65 mN/m or less, and at least a 30% reduction in
surface polarity compared to a control untreated glass surface.
14. The method of claim 13, wherein the method further comprises
applying a cleaning procedure to the glass substrate subsequent to
treating the surface of the glass substrate with the adhesion agent
and prior to applying the black matrix material to the surface of
the glass substrate that is treated with the adhesion agent.
15. The method of claim 12 wherein treating the surface of the
glass substrate with the adhesion agent provides at least a 30%
reduction in the polar component of the overall surface energy of
the glass substrate as determined by water and diiodomethane
contact angle measurements relative to a non-treated, control glass
substrate.
16. The method of claim 12 wherein treating the surface of the
glass substrate with the adhesion agent increases the water contact
angle of the glass substrate by at least two times relative to the
non-treated, control glass substrate.
17. The method of claim 12, wherein the adhesion agent is applied
using a plasma deposition method.
18. A method of improving the adhesion of black matrix on a glass
substrate, the method comprising: providing a glass substrate;
treating a surface of the glass substrate with an adhesion agent,
wherein the adhesion agent will increase the water contact angle of
the glass surface to at least 40.degree.; applying black matrix to
the surface of the glass substrate that is treated with the
adhesion agent; and creating a pattern within the black matrix,
wherein the pattern includes one or more black matrix segments and
at least one or more black matrix segments has a line width of less
than 8 .mu.m.
19. The method of claim 18 wherein treating the surface of the
glass substrate with the adhesion agent provides at least one of: a
total surface energy of the glass substrate of 65 mN/m or less; and
at least a 30% reduction in surface polarity compared to a control
untreated glass surface, as determined by water and diiodomethane
contact angle measurements.
20. The method of claim 18 wherein treating the glass substrate
with the adhesion agent increases the interfacial tension between a
developing solution and the treated glass substrate by at least
five times relative to a non-treated, control glass substrate.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of priority of U.S.
Provisional Application Ser. No. 61/975,160 filed on Apr. 4, 2014
the content of which is relied upon and incorporated herein by
reference in its entirety.
TECHNICAL FIELD
[0002] The present disclosure relates generally to patterned
articles and more particularly to patterned articles comprising
glass substrates and black matrix segments, wherein the black
matrix segments are in the form of a pattern.
BACKGROUND
[0003] Display devices, especially a flat panel display such as a
liquid crystal display (LCD) include a thin film transistor (TFT)
in each pixel to drive the display device with each pixel having a
dimensional size of several microns. Moreover, a plurality of
pixels is arranged in a patterned matrix such as a grid-like
structured pattern. Alternative light sources for flat panel
displays include light-emitting diodes (LED) and the next
generation organic light-emitting diodes (OLED). Like the pixel
matrix, the LEDs are arranged in a patterned matrix. The light
produced by each pixel or light-emitting diode is then directed to
a color filter array that includes color filter units, e.g., red,
green or blue (RGB) units. Like the pixels, the color filter array
is also arranged in a patterned matrix such that each pixel is
generally associated with an individual color unit.
[0004] One method for producing an LCD or LED color filter array
involves utilizing an ink jet system to "print" RGB color inks into
the individualized color units on a glass substrate. In this
method, a polymer composition, hereafter, and at times referred to
as "black matrix" is deposited onto a glass sheet in liquid form,
pre-baked to evaporate solvents, patterned into an array of wells
separated by raised walls by partially curing with ultraviolet
light through a mask, developed with an alkaline solution to create
the well array pattern, and then post-baked. The pattered glass
substrate is then passed under an ink jet head, and very small
quantities of colored ink are placed or printed into each of the
wells to form the individualized RGB color units. The raised walls
surrounding each well serve to contain the color filter ink printed
into that well until the ink has dried, thereby preventing
intermixing of the different colored inks.
[0005] The continuing demand for high picture quality, high
resolution display devices will always require a greater density of
pixels for a given area as well as black matrix patterns of smaller
dimensions for the color filter array. There are, however, current
technical limitations as to how small one can pattern black matrix
in terms of line width without having the polymer material
delaminate from the glass substrate during the development process.
The current industry standard of black matrix line width is
approximately 5 .mu.m to 8 .mu.m. However, display manufacturers
are forever looking to increase display resolution, and therefore,
there is a continued interest and technical objective to reduce
black matrix line widths to 5 .mu.m or less.
SUMMARY
[0006] Embodiments disclosed herein include a patterned article
that comprises a glass substrate and black matrix segments. The
black matrix segments are in the form of a pattern of wells which
are separated by line segments having a width of less than 8 .mu.m.
The article also comprises an adhesion agent positioned between the
glass substrate and the black matrix polymer. The adhesion agent
provides at least one of: a total surface energy of the glass
substrate of 65 mN/m or less; and at least a 30% reduction in
surface polarity compared to a control untreated glass surface, as
determined by water and diiodomethane contact angle measurements
and application of the Wu model for calculation of surface
energy.
[0007] Embodiments disclosed herein also include a method of
improving the adhesion of black matrix to a glass substrate. The
method comprises providing a glass substrate, and treating a
surface of the glass substrate with an adhesion agent. The adhesion
agent provides a total surface energy of the glass substrate of 65
mN/m or less as determined by water and diiodomethane contact angle
measurements and application of the Wu model for calculation of
surface energy. The method may also include at least a concomitant
35% reduction in surface polarity relative to an untreated surface.
The method further comprises applying black matrix to the surface
of the glass substrate that is treated with the adhesion agent, and
then creating a pattern within the black matrix. The pattern
includes line segments and at least one of the line segments has a
width of less than 8 .mu.m.
[0008] Embodiments disclosed herein may further include another
method of improving the adhesion of black matrix to a glass
substrate. The method comprises providing a glass substrate, and
treating a surface of the glass substrate with an adhesion agent.
The adhesion agent will increase the water contact angle of the
glass surface to at least 40.degree.. The method further comprises
applying black matrix to the surface of the glass substrate that is
treated with the adhesion agent, and then creating a pattern within
the black matrix. The pattern includes line segments and at least
one of the line segments has a width of less than 8 .mu.m.
BRIEF DESCRIPTION OF THE FIGURES
[0009] The accompanying Figures, which are incorporated in and
constitute a part of the specification, illustrate as follows.
[0010] FIG. 1 is a graphical representation of different adhesion
agents applied to a glass substrate, and an observed relationship
in water contact angle of a treated surface of the substrate and
the adhesive character between black matrix and the treated surface
as demonstrated by delamination time in alkaline developer
solution;
[0011] FIG. 2 is a graphical representation of how well the
adhesion agent,
N,N-dimethyl-N-(3-(trimethoxysilyl)propyl)octadecan-1-ammonium
chloride (hereafter, "YSAM C18"), is maintained on a surface of a
glass substrate following several types of wash or clean steps
including air plasma, KOH solution, alkaline detergent solution and
water;
[0012] FIG. 3 is a graphical representation of different adhesion
agents, i.e., alkyl ammonium compounds with varying alkyl chain
length, and how each compound is maintained on a glass substrate
surface for three different washing process cycles;
[0013] FIG. 4 is a graphical representation of observed differences
in delamination time for two adhesion agents, octadecyl ammonium
chloride and YSAM C18, that are applied to a glass substrate,
followed by contacting the treated surface with two different
developer solutions; and
[0014] FIG. 5 is a graphical representation of black matrix
adhesion performance determined by the percentage of 4 .mu.m
unanchored black matrix lines which remain adhered to the glass
surface after 150 seconds of exposure to an alkaline developer
solution as a function of total surface energy. The linear
regression applies only to surface treatments which are covalently
bound to the glass surface.
DETAILED DESCRIPTION
[0015] The commercial market for high resolution video displays is
competitive, and display manufacturers are always looking to
provide the next generation technology to their customers. There
are, however, technical hurdles that must be addressed before
greater resolution displays are brought to the market. One problem
that display manufacturers experience in manufacturing ever smaller
color filter arrays is delamination of black matrix from the
surface of a glass substrate when the black matrix pattern contains
line segments having widths below approximately 8 .mu.m or 6 .mu.m,
and particularly below 5 .mu.m. It is proposed that the
delamination is the result of a development or wash step, e.g., an
alkaline wash, in the lithographic process. Seepage of developer
solution at the black matrix-glass interface can result in
undercutting of the black matrix line segments as line widths are
patterned below the current 5 .mu.m to 8 .mu.m industry standard. A
modification of the surface properties of a glass substrate prior
to the deposition of black matrix is one way to improve upon the
adhesion or retention of black matrix line segments with narrow
widths.
[0016] Described herein is a process to modify the surface
properties of a glass substrate. The process can be used to modify
the surface of a glass substrate that is to be used in the
manufacture of a flat panel video display, e.g., in the making of a
color filter array for a flat panel display. The flat panel
displays or color filter arrays that can benefit from such a
process can range from relatively small displays, e.g., camera and
smart phone displays, to medium sized displays, e.g., tablets and
laptops, and to relatively large displays, e.g., televisions. The
glass substrates modified by the process described can be used to
manufacture various types of displays including LCD, LED and OLED.
In particular, the glass substrates modified by the process
described can be used to manufacture a color filter array that is a
required component for each of the above stated displays.
[0017] The process is directed to a glass substrate that is treated
with an adhesion agent to modify the surface properties of the
substrate. It is believed that the adhesion agent is used to
"prime" the glass surface for deposition of black matrix, and
therefore, improve upon the adhesion or retention properties of the
black matrix material to the glass substrate. As stated, improved
adhesion is required to minimize delamination of segments of
patterned black matrix during the development process,
particularly, if the black matrix pattern includes line segments
with widths less than approximately 8 .mu.m, and in many instances,
line segments with widths less than 6 .mu.m or less than 5 .mu.m.
Surface treatments that can be used to improve upon black matrix
adhesion and retention of segment line widths of less than 8 .mu.m
are generally associated with organic-based adhesion agents that
can impart greater hydrophobic character to a surface of a
well-cleaned glass substrate, the latter of which is hydrophilic by
nature. A glass surface with enhanced hydrophobic character is
believed to enhance the interfacial compatibility of black matrix
polymers that are also hydrophobic in character.
[0018] In one aspect, the application of an adhesion agent to a
surface of a glass substrate can offer some chemical or physical
interaction between the glass surface and the black matrix
material. The degree of chemical bonding will depend on the
specific organic functionality of the adhesion agent. In the case
of a chemical interaction, one can use an adhesion agent having
reactive functionality that can form a covalent bond with a
component of the black matrix material as it is cured. Potential
reactive functionality of an adhesion agent can include, but not be
limited to, a vinyl or acrylate group, that can covalently bound
with other vinyl or acrylate monomers or oligomers in a black
matrix polymer composition. The ability of the adhesion agent to
chemically interact with black matrix can also enhance the
curing/polymerization of the black matrix polymer at or near the
glass surface interface. In the case of a physical interaction, one
can use an adhesion agent having relatively long, straight or
branched, chains that can potentially penetrate into the black
matrix material at or near the glass-black matrix interface prior
to or during cure.
[0019] In another aspect, the application of an adhesion agent to a
surface of a glass substrate can increase chemical resistance to
the aqueous developer solution at the glass/black matrix interface.
All of the above stated physical and chemical modifications
incurred by treating a surface of a glass substrate with an
adhesion agent can alone or in combination contribute to the
observed improvement in minimizing the delamination of black matrix
segments during the development process.
[0020] The term "treating" a surface of a glass substrate with an
adhesion agent can include coating a glass substrate with the
adhesion agent. In other words, the amount of adhesion agent used
in treating a glass substrate can determine whether or not the
adhesion agent would establish a coating. In some instances, a
coating established by the application of an adhesion agent can be
referred to as a prime coat for the glass substrate prior to the
deposition of black matrix. In other instances, treating a surface
of a glass substrate with an adhesion agent does not form a
continuous coating. In other words, a surface of a glass substrate
is spot treated with an adhesion agent, and so there are areas on
the surface of the glass substrate that have no adhesion agent.
[0021] It must be noted that, as used in the specification and the
appended claims, the singular forms "a," "an" and "the" include
plural referents unless the context clearly dictates otherwise.
Thus, for example, reference to "an adhesion agent" includes
mixtures of two or more adhesion agents, and the like. "Optional"
or "optionally" means that the subsequently described event or
circumstance can or cannot occur, and that the description includes
instances where the event or circumstance occurs and instances
where it does not. It will be further understood that the endpoints
of each of the ranges are significant both in relation to the other
endpoint, and independently of the other endpoint. It is also
understood that there are a number of values disclosed herein, and
that each value is also herein disclosed as "about" that particular
value in addition to the value itself. For example, if the value
"10" is disclosed, then "about 10" is also disclosed. It is also
understood that throughout the application, data is provided in a
number of different formats, and that this data, represents
endpoints and starting points, and ranges for any combination of
the data points. For example, if a particular data point "10" and a
particular data point "15" are disclosed, it is understood that 10
and 15 are considered disclosed. It is also understood that each
unit value between two particular unit values are also disclosed.
For example, if 10 and 15 are disclosed, then 11, 12, 13, and 14
are also disclosed.
[0022] The described process provides an article patterned with
black matrix. The article comprises: a glass substrate; patterned,
black matrix segments; and an adhesion agent positioned between the
glass substrate and the patterned black matrix segments. As stated,
black matrix is in the form of a developed pattern that includes
line segments, and at least one segment has a line width of 8 .mu.m
or less, for example in the range of 0.01 .mu.m to 8 .mu.m, 0.1
.mu.m to 6 .mu.m, 0.5 .mu.m to 6 .mu.m, 0.5 .mu.m to 4 .mu.m, or in
the range of 0.5 .mu.m to 3 .mu.m. As stated above, it is an
objective to reduce the relative degree of delamination of black
matrix segments from a surface of a glass substrate by treating a
surface of the glass substrate with an adhesion agent. Moreover,
the problem associated with delamination of black matrix segments
is generally associated with segments of black matrix with narrow
line widths. Accordingly, the process is particularly helpful in
forming segments of black matrix having a line width in the range
of 1 .mu.m to 4 .mu.m, e.g., below the current industry standard
line width. It is of course understood by a person of skill in the
art that the described process will also improve upon the adhesion
characteristics of the patterned segments with the surface of a
glass substrate no matter what the line width, even current
segments with line widths of 5 .mu.m to 10 .mu.m, e.g., 8
.mu.m.
[0023] The segments of patterned black matrix can form a grid-like
structure that includes segments oriented in a first direction and
segments oriented in a second direction. The first and the second
direction segments can intersect to form any angle of orientation
in the range of 45.degree. to 120.degree.. For example, a simple
grid-like structure would have an angle of orientation of about
90.degree., a triangular pattern would have an angle of orientation
of about 60.degree., and a hexagonal pattern would have an angle of
orientation of about 120.degree.. Also, a person of skill would
understand that the minimal line width of any one segment is
limited by physical stability of the patterned black matrix on the
glass substrate, particularly, as the black matrix is being
developed. Accordingly, the line width of any one segment will
likely have a minimum line width of 0.1 .mu.m, more likely of 0.5
.mu.m.
[0024] In many instances, and to take full advantage of the process
described herein, the segments in a first direction or a second
direction will have a line width that is not greater than 5 .mu.m,
and more likely not greater than 4.5 .mu.m, not greater than 4.0
.mu.m, not greater than 3.5 .mu.m, not greater than 3.0 .mu.m, not
greater than 2.5 .mu.m or not greater than 2.0 .mu.m.
[0025] The use of contact angle analysis is an established method
to determine surface energy of solid surfaces. One technique
involves acquiring the contact angle between the surface and
different probe liquids; the latter having well-defined surface
energy components. Various models exist to approximate the surface
energy based on a 2-fluid method. Those models include the Wu
method, Owens-Wendt-Rabel-Kaelble method, and the van Oss method.
The Wu method is described, for example, in S. Wu, "Calculation of
interfacial tension in polymer systems", Journal of Polymer Science
Part C: Polymer Symposia, 34 (1971) 19-30, the entire disclosure of
which is incorporated herein by reference. The Owens-Rabel-Kaelble
method is describe, for example, in D. K. Owens, R. C. Wendt,
"Estimation of the surface free energy of polymers", Journal of
Applied Polymer Science, 13 (1969) 1741-1747, the entire disclosure
of which is incorporated herein by reference. The Van Oss method is
described, for example, in C. J. Van Oss, M. K. Chaudhury, R. J.
Good, "Interfacial Lifshitz-van der Waals and polar interactions in
macroscopic systems", Chemistry Reviews, 88 (1988) 927-940, the
entire disclosure of which is incorporated herein by reference. The
values presented herein involve determination of dispersive, polar,
and total surface energies using the Wu method, as set forth below.
It is understood that the use of the other models may result in
different absolute values for dispersive, polar and total surface
energies.
[0026] Surface Energy Theory and Equations
TABLE-US-00001 List of Symbols .gamma..sub.l Total surface energy
of the liquid (mN/m) .gamma..sub.s Total surface energy of the
solid (mN/m) .gamma..sub.l.sup.d Dispersive surface energy
component of the liquid (mN/m) .gamma..sub.s.sup.d Dispersive
surface energy component of the solid (mN/m) .gamma..sub.l.sup.p
Polar surface energy component of the liquid (mN/m)
.gamma..sub.s.sup.p Polar surface energy component of the solid
(mN/m) .theta. Contact angle between the probe liquid/surface/air
(.degree.)
[0027] The surface energy values presented herein are calculated
using the Wu method to estimate the surface energy, using the
following equation:
.gamma. l ( cos .theta. + 1 ) = 4 [ .gamma. l d .gamma. s d .gamma.
l d + .gamma. s d ] [ .gamma. l p .gamma. s p .gamma. l p + .gamma.
s p ] ##EQU00001##
[0028] Here it is understood that the total surface energy of the
liquid and solid is the sum of the polar and dispersive components.
In order to apply this model, we used water [.gamma..sub.l=72.8
mN/m; .gamma..sup.d.sub.l=26.4 mN/m; .gamma..sup.p.sub.l=46.4 mN/m]
and diiodomethane (DIM) [.gamma..sub.l=50.8 mN/m;
.gamma..sup.d.sub.l=50.8 mN/m; .gamma..sup.p.sub.l=0.0 mN/m] as
probe liquids. Because DIM expresses dispersion forces only, the Wu
model was used to first approximate the dispersive term for the
surface; all polar components dropped out of the equation. Next,
the surface energy and contact angle values for pure water were
used along with the calculated dispersive term to approximate the
polar component. Finally, the sum of the polar and dispersive terms
provided the total surface energy.
[0029] Liquid surface energies can be determined by methods well
known to those in the art including the pendant drop method, the du
Nuoy ring method or the Wilhelmy plate method as described in
Physical Chemistry of Surfaces, Arthur W. Adamson, John Wiley and
Sons, 1982, pp. 28, the entire disclosure of which is incorporated
herein by reference. A common method derived by Fowkes utilizes a
combination of Wilhelmy plate and contact angle on PTFE to
differentiate the polar and dispersive components of each liquid.
Fowkes surface energy theory dictates that the dispersive component
of the liquid [.gamma..sub.l.sup.d] can be determined from the
total surface energy [.gamma..sub.l] and the contact angle of the
liquid on a PTFE surface [.theta..sub.PTFE].
.gamma. l d = .gamma. l 2 ( cos .theta. PTFE + 1 ) 2 72
##EQU00002##
[0030] The polar and nonpolar components of the surface energy can
then be used to calculate the interfacial energy by the method of
Fowkes as described in Physical Chemistry of Surfaces, Arthur W.
Adamson, John Wiley and Sons, 1982, pp. 357, the entire disclosure
of which is incorporated herein by reference, and the following
equation:
.gamma..sub.ij=/.gamma..sub.i+.gamma..sup.j-2(.gamma..sub.i.sup.d.gamma.-
.sub.j.sup.d).sup.1/2-2(.gamma..sub.i.sup.p.gamma..sub.j.sup.p).sup.1/2
Here .gamma..sub.ij is the interfacial tension between components i
and j, .gamma..sub.l is the surface energy of i,
.gamma..sub.i.sup.d is the dispersive component of the surface
energy of i, and .gamma..sub.i.sup.p is the polar component of the
surface energy of i, .gamma..sub.j is the surface energy of j,
.gamma..sub.j.sup.d is the dispersive component of the surface
energy of j, and .gamma..sub.j.sup.p is the polar component of the
surface energy of j.
[0031] Accordingly, one can determine the surface properties of a
non-treated (control) glass substrate as well as the surface
properties of a glass substrate treated with an adhesion agent by
measuring water and DIM contact angles of each substrate using any
one of the surface energy models described above.
[0032] The propensity for a black matrix segment to delaminate from
a glass substrate in the presence of a developing or wash solution
can be described by a quality factor f, which is the ratio of the
work of adhesion (W.sub.l12) between the black matrix material and
the glass substrate in the presence of a developing solution (l) to
the work of adhesion (W.sub.a12) between the black matrix material
and the glass substrate in air, as described by
f = W l 12 W a 12 ##EQU00003##
See, Bauer, Drescher and Illig, "Surface Tension, adhesion and
wetting of materials for the photolithographic process" Journal of
Vacuum Science and Technology, B, 14, 2485, (1996), the entire
disclosure of which is incorporated herein by reference. Work of
adhesion in air is based on the surface energies of the black
matrix material (.gamma..sub.1) and the glass substrate
(.gamma..sub.2), and their interfacial tension (.gamma..sub.12).
Work of adhesion in a liquid (.gamma..sub.3), such as the
developing solution is based on the interfacial tension of the
black matrix material and liquid (.gamma..sub.13), the interfacial
tension of the glass substrate and the liquid (.gamma..sub.23), and
the interfacial tension between black matrix and glass substrate
(.gamma..sub.12).
W a 12 = .gamma. 1 + .gamma. 2 - .gamma. 12 ##EQU00004## W l 12 =
.gamma. 13 + .gamma. 23 - .gamma. 12 ##EQU00004.2## .gamma. ij =
.gamma. i + .gamma. j - 4 [ .gamma. i d .gamma. j d .gamma. i d +
.gamma. j d + .gamma. i p .gamma. j p .gamma. i p + .gamma. j p ]
##EQU00004.3##
From the discussion above, one must also recognize that the
particular solution utilized to develop the black matrix pattern
will also affect the black matrix delamination behavior.
[0033] Adhesion Agents
[0034] The adhesion agent used in the process will possess a dual
adhesive or attractive functionality meaning that one portion of
the agent is attractive to the glass substrate and another portion
of the agent is attractive to the black matrix material. We know
that a clean pristine surface of a glass substrate includes
silicon-oxide or silicon-hydroxy groups at or near the surface.
Accordingly, a surface of a glass substrate is generally considered
to have some degree of hydrophilic character. We also know that the
black matrix materials commonly used in the flat panel display
industry are generally organic polymers that are deposited as a
film on a glass substrate, overlaid with a photo mask and then
cured or crosslinked. The black matrix composition is thus
considered to have some degree of hydrophobic character.
Accordingly, an adhesion agent will generally have a regional or
group functionality that is considered to be more hydrophilic as
well a regional or group functionality that is considered to be
more hydrophobic. It is to be understood that the terms
"hydrophilic" and "hydrophobic" are well known terms that are used
by scientists on a relative comparative scale, and refers to how
well a particular compound, or more importantly a surface, repels
or attracts water. One physical test method a scientist can use to
help quantify a relative degree of hydrophilic/hydrophobic
character of a particular surface is by measuring the water contact
angle of the surface.
[0035] Fatty Chain Functional Organics
[0036] One class of adhesion agents can be referred to as a fatty
chain, functional organic agent. A fatty chain functional organic
agent will have an alkyl portion that includes from six to thirty
carbon atoms, and a functional group. The alkyl portion would be
attracted to the black matrix and the functional group would be
attracted to a surface of a glass substrate. In theory, the fatty
chain, functional organic agent would physically or chemically
interact with both the black matrix and the glass substrate to
enhance the attraction of the black matrix to the glass substrate
at the black matrix-glass interface. The alkyl portion is believed
to extend from a surface of the glass substrate and interact with
the black matrix. The functional group is generally associated as
polar in character, meaning the functional group would be attracted
to a hydrophilic surface of the glass. The functional group(s) of
the fatty chain include, but are not limited to, an amine, an
alcohol, an epoxy, an acid or a siloxane. Accordingly, the adhesion
agent is a fatty chain, functional organic agent selected from the
group consisting of (C.sub.6-C.sub.30)alkyl amine,
(C.sub.6-C.sub.30)alkyl alcohol, (C.sub.6-C.sub.30)alkyl acid, and
(C.sub.6-C.sub.30)alkyl siloxane. A (C.sub.6-C.sub.30)alkyl acid
includes, but is not limited to, carboxylic acids, organic sulfonic
acids, and organic phosphonic acids. The term "siloxane" can be
defined by group formula
--Si(R.sup.1).sub.3-n(OR.sup.2).sub.n
wherein R.sup.1 is an alkyl or lower alkyl; R.sup.2 is a lower
alkyl and n is 1, 2. Also, it is understood by a person of skill in
the art that because many of the siloxane-based adhesion agents are
prepared as aqueous solutions, see e.g., Example 3, one would
expect at least some hydrolysis of the alkoxy substituents in such
a preparation prior to contact with the glass substrate.
[0037] The term "alkyl" as used herein is a linear or branched
saturated hydrocarbon of 1 to 30 carbon atoms, such as methyl,
ethyl, n-propyl, isopropyl, n-butyl, isobutyl, t-butyl, pentyl,
hexyl, heptyl, octyl, decyl, tetradecyl, hexadecyl, eicosyl,
tetracosyl and the like. A "lower alkyl" group is an alkyl group
containing from 1 to 5 carbon atoms. Some examples of lower alkyls
include, but not limited to, methyl, ethyl, propyl, iso-propyl, and
n-butyl. Accordingly, a (C.sub.6-C.sub.30) alkyl is an alkyl group
with six to thirty carbon atoms.
[0038] 2. Substituted Alkyl Silanes
[0039] A substituted alkyl silane is similar in structure to an
alkyl siloxane referred to above with the exception that the alkyl
is also substituted with one or more organic functional groups
selected from the group consisting of amino, ammonium, hydroxyl,
ether and carboxylic acid. In many instances, the substituted alkyl
silane is substituted with an organic functional group positioned
at a terminal end of the alkyl group or anywhere along or within
the alkyl chain. Also, in many instances the substituted alkyl is a
substituted lower alkyl. Some exemplary substituted lower alkyl
silanes include, but are not limited to,
.gamma.-aminopropyltriethoxy silane, .gamma.-aminopropytrimethoxy
silane, .beta.-aminoethyltriethoxy silane, and
.delta.-aminobutyltriethoxy silane. A substituted alkyl silane of
particular interest will include one or more functional groups
selected from the group consisting of quaternary nitrogen, ether
and thioether. In many, instances, the substituted alkyl silane
includes a pendant (C.sub.6-C.sub.30) alkyl that extends from the
functional group. Of particular interest is a substituted alkyl
silane with a quaternary nitrogen and having a pendant
(C.sub.10-C.sub.24) alkyl. An exemplary substituted alkyl silane of
interest is
N,N-dimethyl-N-(3-(trimethoxysilyl)propyl)octadecan-1-ammonium
chloride, often abbreviated herein as YSAM C18, the chemical
structure of which is indicated below. YSAM C14 and YSAM C1 are
also represented below. YSAM C18 has a pendant (C.sub.18)alkyl off
a quaternary nitrogen. Likewise, YSAM C14 has a pendant
(C.sub.14)alkyl off a quaternary nitrogen.
##STR00001##
[0040] 3. Bridged Disilane
[0041] Another class of adhesion agent includes bridged disilanes.
A bridged disilane will have a general formula I
(R.sup.2).sub.3Si--X--Si(R.sup.2).sub.3 I
wherein R.sup.2 is a lower alkyl, X is NH or O. A class of bridged
disilanes are referred to as disilazanes where X is NH.
[0042] 4. Other Silane Agents
[0043] There are also some proprietary silane-based compounds that
improve the adhesion characteristics of the black matrix to a glass
substrate. As with the other adhesion agents, the proprietary
silane-based compounds can reduce the overall surface energy of the
glass substrate to below 65 mN/m and reduce the polar component of
the surface energy by at least 30%.
[0044] 5. Reactive Functional Silanes
[0045] Another class of adhesion agent can be referred to as a
reactive functional alkyl silane. A reactive functional alkyl
silane is similar to an alkyl silane described above with the
exception that the alkyl portion of the compound includes a site of
reactive functionality, which in theory can participate in a
covalent chemical reaction, e.g., as a crosslink, with black
matrix. As understood by those in the photolithographic art, a
black matrix material can include one or more acrylic polymers that
can form a chemical bond with the functional site of the silane
following a thermal or photo cure. Like the acrylic black matrix
material, the functional silane can comprise like reactive
functionality, e.g., vinyl, acrylic, epoxide, that can possibly
react with a component of the black matrix. Again, the silane
portion of the functional silane is believed to have some
attraction or interaction to a surface of the glass substrate.
[0046] One type of functional silane is an alkyl silane containing
an epoxy group. An epoxy silane refers to compounds that on the one
hand possess at least one epoxy ring and at the same time display
groups that form silanol structures under hydrolysis conditions. A
more general description of epoxy silanes and a method of making
these compounds is provided in U.S. Pat. No. 2,946,701. These are
compounds having the general formula (II) or (III):
##STR00002##
wherein R.sup.3 is a divalent hydrocarbon radical with a maximum of
twelve carbon atoms and the hydrocarbon radical optionally includes
an ether linkage, e.g., --CH.sub.2OCH.sub.2CH.sub.2CH.sub.2--;
R.sup.4 is a lower alkyl; and m is an integer from 1 to 10.
Particularly preferred epoxy silanes are such compounds in which
R.sup.4 is methyl or ethyl. Exemplary epoxy silanes include, but
are not limited to, 3-glycidyl oxypropyl trimethoxysilane and
2-(3,4-epoxycyclohexyl) ethyl trimethoxysilane.
[0047] Another type of functional silane is a vinyl silane, a
compound having a silane group and an alkyl vinyl group, i.e., an
alkyl with at least one carbon-carbon double bond. In theory, the
compound is attracted to the surface of a glass substrate by the
silane group, and binds to the through the vinyl functionality,
thereby improving the adhesion between the black matrix material
and the glass substrate. One exemplary compound is prepared from
the reaction of bis-3-(aminopropyl) tetramethylsiloxane and
glycidyl methacrylate.
[0048] Still another type of functional silane is one with a
functional (meth)acryloyl group that is connected to a polysiloxane
chain through a divalent organic radical. Specific examples of
these compounds are represented by general formula IV.
##STR00003##
wherein R.sup.5, R.sup.6 and R.sup.7 are independently selected
from a lower alkyl; p is an integer from 3 to 20; X represents a
divalent connecting group, and specifically represents a connecting
chain represented by the formulas: CH.sub.2CH(OH)CH.sub.2--,
--(CH.sub.2).sub.nNHCH.sub.2CH(OH)CH.sub.2--, --(CH.sub.2).sub.n,
--(CH.sub.2).sub.n--O--(CH.sub.2).sub.m-- or
--OCH.sub.2CH(OH)CH.sub.2--, and n and m respectively represent an
integer from 2 to 6.
[0049] 6. Functional Polymers
[0050] Another class of adhesion agent is commonly referred to as a
functional polymer. The term "polymer" as used herein includes a
homopolymer (a polymer prepared form a single monomer) and a
copolymer (a copolymer prepared from at least two monomers). The
term "polymer" also makes no reference to the number average
molecular weight (MW.sub.n) of the polymer, and so includes
polymers with very large MW.sub.n as well as very small MW.sub.n
polymers (i.e., oligomers), and those polymers having a MW.sub.n
that falls in between.
[0051] In one embodiment, a functional polymer will have a diblock
structure AB where A is a hydrophobic block and B is a hydrophilic
block. The term "amphiphilic polymer" is also commonly used to
describe such a polymeric structure. Exemplary hydrophilic blocks
of a functional polymer can be prepared from a variety of known
hydrophilic polymers including, but not limited to, cellulose,
polysaccharide, polyvinyl alcohol, polycarboxylic acid,
poly(meth)acrylic acid, polyethylenglycols (PEG), polyamides,
polyacrylic amides, polyhydroxyethylmethacrylate (HEMA),
polyethyleneglycol(meth)acrylate, and
polyethoxypolyethyleneglycol(meth)acrylate, As used herein
(meth)acrylate refers to an acrylate and the corresponding
methacrylate.
[0052] The hydrophilic block(s) in the amphiphilic block copolymers
may also be prepared from different monomers, or oligomers, for
example the monomer or oligomers used for the preparation of the
above mentioned hydrophilic polymer blocks, or monomers selected
from acrylic acid, maleic acid, hydroxyethylmethacrylate (HEMA),
polyethyleneglycol (meth)acrylate, ethoxypolyethyleneglycol
(meth)acrylate, methoxyethyl (meth)acrylate, ethoxy (meth)acrylate,
2-dimethylamino-ethyl(meth)acrylate (DMAEMA).
[0053] Likewise, exemplary hydrophobic blocks of a functional
polymer can be prepared from known hydrophobic monomers including,
but not limited to, monovinyl aromatic monomers such as styrene and
alpha-alkyllstyrenes, and other alkylated styrenes, or alkyl
(meth)acrylic esters, or vinyl esters. Alternatively, the A block
may be prepared from ethylenically unsaturated monomers chosen from
butadiene, vinyl esters such as vinyl acetate, vinyl versatate and
vinyl propionate. The term "alkyl (meth)acrylic esters" can include
methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate,
n-butyl (meth)acrylate, isobutyl (meth)acrylate, 2-ethylhexyl
(meth)acrylate, lauryl (meth)acrylate, and t-butyl (meth)acrylate.
In addition, hydrophobic block(s) of the amphiphilic polymer can be
prepared with vinyl unsaturated aliphatic hydrocarbon monomers
comprising from 1 to 6 carbon atoms such as polybutylene and
polyisobutylene.
[0054] In another embodiment, a functional polymer is a
polyalkylleneimine. For example, a polyethyleneimines can be
prepared either by ring-opening polymerization of acyl-substituted
oxazolines, with subsequent hydrolysis, or by cationically
initiated polymerization of ethyleneimine (aziridine), the former
case producing a linear polyethyleneimine and the latter case
producing its branched counterpart. Polyethyleneimines are
available commercially, an example being Lupasol.RTM. G20
water-free, Lupasol.RTM. FG, or Lutensol.RTM. FP 620 precursor from
BASF.
[0055] 7. Surfactants
[0056] Another class of adhesion agent is commonly referred to as a
surfactant. Surfactants are generally classified an anionic
surfactant, a cationic surfactant, a nonionic surfactant, and an
amphoteric surfactant. The class of amphoteric surfactants is of
particular interest. An amphoteric surfactant of particular
interest is represented by formula V.
##STR00004##
wherein R.sup.9 is an alkyl group having from 8 to 24 carbon atoms,
preferably an alkyl group having from 8 to 14 carbon atoms, R.sup.8
is an alkyl group having from 1 to 4 carbon atoms, and with methyl
being preferred, and n is 1, 2, 3, 4, or 5. An example of a
preferred compound is
N-decyl-N,N-dimethyl-3-ammonio-1-propane-sulfonate, more commonly
referred to as sulfobetaine 3-10.
[0057] Another amphoteric surfactant of interest is an alkylamido
betaine of formula VI.
##STR00005##
wherein R.sup.8 and R.sup.9 is defined above as in formula VI, and
m and n is independently selected from 1, 2, 3, 4 or 5, and Y is
--SO.sub.3 or --C(O)O. The alkylamido betaines of interest include,
but not limited to, cocoamidopropyl dimethyl betaine and lauroyl
amidopropyl dimethyl betaine.
[0058] In one aspect, when the surfactant is an anionic surfactant,
the anionic surfactant comprises an alkyl aryl sulfonate, an alkyl
sulfate, or sulfated oxyethylated alkyl phenol. Examples of anionic
surfactants include, but are not limited to, sodium dodecylbenzene
sulfonate, sodium decylbenzene sulfonate, ammonium methyl
dodecylbenzene sulfonate, ammonium dodecylbenzene sulfonate, sodium
octadecylbenzene sulfonate, sodium nonylbenzene sulfonate, sodium
dodecylnaphthalene sulfonate, sodium hetadecylbenzene sulfonate,
potassium eicososyl naphthalene sulfonate, ethylamine
undecylnaphthalene sulfonate, sodium docosylnaphthalene sulfonate,
sodium octadecyl sulfate, sodium hexadecyl sulfate, sodium dodecyl
sulfate, sodium nonyl sulfate, ammonium decyl sulfate, potassium
tetradecyl sulfate, diethanolamino octyl sulfate, triethanolamine
octadecyl sulfate, amrnmonium nonyl sulfate, ammonium nonylphenoxyl
tetraethylenoxy sulfate, sodium dodecylphenoxy triethyleneoxy
sulfate, ethanolamine decylphenoxy tetraethyleneoxy sulfate, or
potassium octylphenoxy triethyleneoxy sulfate.
[0059] Examples of nonionic surfactants include, but are not
limited to, the condensation product between ethylene oxide or
propylene oxide with propylene glycol, ethylene diamine, diethylene
glycol, dodecyl phenol, nonyl phenol, tetradecyl alcohol,
N-octadecyl diethanolamide, N-dodecyl monoethanolamide,
polyoxyethylene sorbitan monooleate, or polyoxyethylene sorbitan
monolaurate. Other known nonionic surfactants include a class of
surfactants based on blocks of polyalkylene oxide-polyethylene
oxide such as the common Pluronic.RTM. series of surfactants based
on alternating blocks of polypropylene oxide
(A-block))-polyethylene oxide (b-block) having the structure BAB or
ABA. Another example of a nonionic surfactant is an ethoxylated
amine surfactant comprising a hydrophobic tail, e.g., a long chain
alkyl or a corresponding partially unsaturated long chain alkene,
and hydrophilic tail(s) of polyethylene oxide.
[0060] Examples of cationic surfactants include, but are not
limited to, ethyl-dimethylstearyl ammonium chloride,
benzyl-dimethyl-stearyl ammonium chloride, benzyldimethyl-stearyl
ammonium chloride, trimethyl stearyl ammonium chloride,
trimethylcetyl ammonium chloride, dimethylethyl dilaurylammonium
chloride, dimethyl-propyl-myristyl ammonium chloride, or the
corresponding bromide, methosulfate or acetate.
[0061] The process of manufacturing an upper plate of a light
display including the making of a conventional color filter array
is well known. The method of making a color filter array for a
display device includes the steps of plating or depositing a
polymeric black matrix ink on a surface of a glass substrate, and
patterning the ink so as to form patterned segments on the glass
substrate. The pattern step typically requires applying a
pre-defined photo mask atop of the deposited ink and photo curing
exposed portions of the ink. The non-exposed portions of the ink
are then removed using one or more developing solutions, and a
likely water rinse step, to form a grid pattern of micron-sized
wells. Each of the wells is then filled with ink, e.g., using an
ink-jet printing process, in alternating colors of red, green and
blue forming a color filter on the glass substrate. Any method of
ink deposition can be used including a dyeing method, a dispersion
method, a spread method, a print method, an ink-jet print method,
or the like. The grid-typed structure of the black matrix pattern
divides each color of the color filter into pixel units on a plane.
A protective transparent layer can then be deposited over the color
filter grid to maintain the physical integrity of the color filter
array. As an example, a brief description of forming a color array
using the pigment dispersion method or the inkjet print method is
described in U.S. Pat. No. 7,050,130 assigned to LG Electronics
Inc.
[0062] Application of Adhesion Agent to Glass Substrate
[0063] The adhesion agent can be applied to the surface of a glass
substrate using techniques known in the art. For example, the
adhesion agent can be applied to a surface of the glass by
spraying, dipping, meniscus coating, flood coating, rollers,
brushes, etc. In one aspect, the adhesion agent is applied by
spraying since the agent can be applied in a spraying station as
glass substrates typically move in a production line in the
manufacturing process. In one embodiment, the adhesive agent is
applied in a continuous horizontal conveyance system or a
continuous vertical conveyance system, where the glass substrate is
oriented in a horizontal (parallel), vertical (perpendicular) or at
any line angle in between. The temperature of the glass substrate
at the time the adhesion agent is applied can be in the range of
from about 10.degree. C. to 300.degree. C. Typically, the adhesion
agent is applied to the surface of the glass at a temperature in
the range of from about 20.degree. C. to 80.degree. C., e.g., at or
near room temperature. In one aspect, the adhesive agent is applied
to the surface of a glass substrate at or about room temperature,
and after the glass surface has been sized, cleaned with various
detergents, rinsed and optionally dried. See, below and
Examples.
[0064] In another aspect, the adhesive agent can be applied to a
surface of a glass substrate at a temperature near or above
175.degree. C., near or above 200.degree. C., or near or above
250.degree. C., where the temperature of the glass is preferably
measured with an infrared detector of the type commonly used in the
art. Application of the adhesive agent at this point in the
manufacturing process can be advantageous because the glass is
virtually free of contaminants, or the adhesive agent could protect
the glass during the remainder of the manufacturing process. In
certain aspects, the glass surface may need to be cleaned prior to
the application of the adhesion agent. This cleaning can be
accomplished by various means including chemical cleaning methods
known in the art and pyrolysis. The objective of these methods is
to expose the hydroxyl groups and siloxane bonds in the glass. The
following cleaning techniques can be used to remove adsorbed
organic molecules from the glass surface. In one aspect, the glass
can be cleaned with an aqueous detergent such as, for example,
SemiClean KG obtained from Yokohama Oils and Fats. In another
aspect, UV/ozone cleaning can be used to clean the glass. UV/ozone
cleaning is carried out with a low pressure mercury lamp in an
atmosphere containing oxygen. UV/ozone cleaning is described, for
example, in Vig et al., J. Vac. Sci. Technol. A 3, 1027, (1985),
the contents of which are incorporated herein by reference. A low
pressure mercury grid lamp from BHK (88-9102-20) mounted in a steel
enclosure filled with air is suitable for carrying out this
cleaning method. The surface to be cleaned may be placed about 2 cm
from the lamp, which may be activated for about 30 minutes, after
which the glass surface is clean and ready for the application of
the adhesion agent.
[0065] Again, depending upon the amount of adhesion agent that is
used to treat a glass substrate per given surface area, and the
type of adhesion agent used in the process, one can envision the
deposition of a coating of adhesion agent. In such an instance,
following an appropriate drying step, the coating produced on the
surface of the glass substrate will have thickness that will vary
from 0.1 nm to 3 .mu.m, 1 nm to 1 .mu.m, or 1 nm to 0.5 .mu.m. The
glass can be rinsed after the adhesion agent has been applied after
the drying step. For example, this rinsing can remove the bulk of
any excess adhesion agent.
[0066] According to various embodiments, the adhesion agent may
also be applied using a plasma deposition method, wherein the
plasma comprises, for example, at least one hydrocarbon component.
For instance, the plasma may be scanned over the surface of the
glass substrate using any method or device known in the art, e.g.,
a plasma jet or torch, such that the surface comes into contact
with one or more of the components making up the plasma, such as
the at least one hydrocarbon component.
[0067] As used herein, the terms "plasma," "atmospheric plasma,"
and variations thereof are intended to denote a gas that passes
through an incident high frequency electric field. Encountering the
electromagnetic field produces ionization of the gas atoms and
frees electrons which are accelerated to a high velocity and, thus,
a high kinetic energy. Some of the high velocity electrons ionize
other atoms by colliding with their outermost electrons and those
freed electrons can in turn produce additional ionization,
resulting in a cascading ionization effect. The plasma thus
produced can flow in a stream and the energetic particles caught in
this stream can be projected toward an object, e.g., the glass
substrate.
[0068] The plasma can, in various embodiments, be an atmospheric
pressure (AP) plasma and a thermal or non-thermal plasma, such as
CVD in vacuum condition. For example, the temperature of the plasma
can range from room temperature (e.g., approximately 25.degree. C.)
to higher temperatures, such as up to about 300.degree. C. By way
of non-limiting example, the temperature of the plasma can range
from about 25.degree. C. to about 300.degree. C., such as from
about 50.degree. C. to about 250.degree. C., or from about
100.degree. C. to about 200.degree. C., including all ranges and
subranges therebetween. The plasma can comprise at least one gas
chosen from argon, helium, nitrogen, air, hydrogen, water vapor,
and mixtures thereof, to name a few. According to some embodiments,
argon can be employed as the plasma gas.
[0069] In non-limiting embodiments, the plasma may also comprise at
least one hydrocarbon, which may be present in the form of a gas.
Suitable hydrocarbons may include, but are not limited to,
C.sub.1-C.sub.12 hydrocarbons, such as methane, ethane, propane,
butane, pentane, hexane, heptane, octane, nonane, decane, undecane,
dodecane, phenyl, double bond or trip bond hydrocarbon and
combinations thereof, to name a few. According to various
embodiments, volatile hydrocarbons with low boiling points (e.g.,
less than 100.degree. C.) may be used, for example, C.sub.1-C.sub.6
hydrocarbons. In still further embodiments, the hydrocarbon can be
methane or ethane. The plasma can comprise, for instance, from
about 1% to about 20% by volume of the at least one hydrocarbon,
such as from about 2% to about 18%, from about 3% to about 15%,
from about 4% to about 12%, from about 5% to about 10%, or from
about 6% to about 8%, including all ranges and subranges
therebetween. The plasma should also comprise at least organics
that has fluorine in hydrocarbon chain, such as fluorine-containing
organics as described elsewhere herein.
[0070] Contact between the plasma and the glass surface can be
achieved using any suitable means known in the art, for example, a
plasma jet or torch can be used to scan the surface of the glass
substrate. The scan speed can be varied as necessary to achieve the
desired coating density and/or efficiency for a particular
application. For example, the scan speed can range from about 5
mm/s to about 100 mm/s, such as from about 10 mm/s to about 75
mm/s, from about 25 mm/s to about 60 mm/s, or from about 40 mm/s to
about 50 mm/s, including all ranges and subranges therebetween.
[0071] The residence time, e.g. time period during which the plasma
contacts the glass surface can likewise vary depending on the scan
speed and the desired coating properties. By way of a non-limiting
example, the residence time can range from less than a second to
several minutes, such as from about 1 second to about 10 minutes,
from about 30 seconds to about 9 minutes, from about 1 minute to
about 8 minutes, from about 2 minutes to about 7 minutes, from
about 3 minutes to about 6 minutes, or from about 4 minutes to
about 5 minutes, including all ranges and subranges therebetween.
In various embodiments, the glass surface can be contacted with the
plasma in a single pass or, in other embodiments, multiple passes
may be employed, such as 2 or more passes, 3 or more passes, 4 or
more passes, 5 or more passes, 10 or more passes, 20 or more
passes, and so on.
[0072] Prior to contact with the plasma, the glass substrate may be
processed using one or more optional steps, such as polishing,
finishing, and/or cleaning the surface(s) or edge(s) of the glass
substrate.
[0073] Glass Substrate
[0074] The glass substrate can be formed by several different
processes, including float processes, slot-draw processes, and
fusion draw processes. See, for example, U.S. Pat. Nos. 3,338,696
and 3,682,609. In the slot-draw and fusion draw processes, the
newly-formed glass sheet is oriented in a vertical direction. One
preferred glass substrate is commonly referred to as 7059 glass
manufactured by Corning Incorporated. The 7059 glass has a small
coefficient of thermal expansion, is superior in dimensional
stability and workability at relatively high processing
temperatures and contains little, if any, alkali component in the
glass. Preferred glass substrates, may, for example, include the
Eagle XG.RTM. and Lotus.RTM. families of display glasses
manufactured by Corning Incorporated. Glass substrates of
particular interest to the described include high performance glass
substrates, such as those manufactured by Corning Incorporated. The
glass substrates are specifically designed to be used in the
manufacture of flat panel displays and preferably exhibit densities
of less than 2.45 g/cm.sup.3 and a liquidus viscosity (defined as
the viscosity of the glass at the liquidus temperature) greater
than about 200,000 poises, preferably greater than about 400,000
poises, more preferably greater than about 600,000 poises, and most
preferably greater than about 800,000 poises. Additionally, the
glass substrates preferably exhibit linear coefficients of thermal
expansion over the temperature range of 0 to 300.degree. C. of
28-35.times.10.sup.-7/.degree. C., or of
28-33.times.10.sup.-7/.degree. C., and strain points higher than
about 650.degree. C. The glass substrate preferably have a melting
temperature less than 1700.degree. C. In addition, the glass
substrate preferably exhibits a weight loss of less than 0.5
mg/cm.sup.2 after immersion in a solution of 1 part HF.sub.(aq) (50
wt. %) and 10 parts NH.sub.4F.sub.(aq) (40 wt. %) for 5 minutes at
30.degree. C.
[0075] In one implementation of the described process, the glass
substrate will have the following composition. The major components
of the glass are SiO.sub.2, Al.sub.2O.sub.3, B.sub.2O.sub.3, and at
least two alkaline earth oxides, i.e., MgO, CaO, SrO and/or BaO.
The SiO.sub.2 serves as the basic glass former of the glass. Its
concentration should be greater than 64 mole percent in order to
provide the glass with a density and chemical durability suitable
for a flat panel display glass, e.g., an AMLCD glass, and a
liquidus temperature (liquidus viscosity) which allows the glass to
be formed by a downdraw process (e.g., a fusion process) described
in more detail below. The glass substrate will preferably have a
density less than or equal to 2.45 grams/cm.sup.3, or less than or
equal to 2.41 g/cm.sup.3, a weight loss which is less than or equal
to 0.8 mg/cm.sup.2 when a polished sample is exposed to a 5%
HCl.sub.(aq) solution for 24 hours at 95.degree. C., and a weight
loss of less than 0.5 mg/cm.sup.2 when exposed to a solution of 1
volume of 50 wt. % HF.sub.(aq) and 10 volumes 40 wt. %
NH.sub.4F.sub.(aq) at 30.degree. C. for 5 minutes.
[0076] In terms of an upper limit, the SiO.sub.2 concentration
should be less than or equal to 71 mole percent to allow batch
materials to be melted using conventional, high volume, melting
techniques, e.g., Joule melting in a refractory melter. Preferably,
the SiO.sub.2 concentration is between 66.0 and 70.5 mole percent,
between 66.5 and 70.0 mole percent, or between 67.0 and 69.5 mole
percent. As a result of their SiO.sub.2 content, the glasses of the
invention typically have melting temperatures greater than or equal
to 1600.degree. C. Al.sub.2O.sub.3 is another glass former of the
glasses of the invention. An Al.sub.2O.sub.3 concentration greater
than or equal to 9.0 mole percent provides the glass with a low
liquidus temperature and a corresponding high liquidus viscosity.
The use of at least 9.0 mole percent Al.sub.2O.sub.3 also improves
the glass' strain point and modulus. In order to achieve an
RO/[Al.sub.2O.sub.3] (RO are oxides of Group IIA elements in the
periodic table) ratio greater than or equal to 1.00 (see below),
the Al.sub.2O.sub.3 concentration needs to be kept below 12.0 mole
percent. Preferably, the Al.sub.2O.sub.3 concentration is between
9.5 and 11.5 mole percent. B.sub.2O.sub.3 is both a glass former
and a flux that aids melting and lowers the melting temperature. To
achieve these effects, the glasses of the invention have
B.sub.2O.sub.3 concentrations that are equal to or greater than 7.0
mole percent. Large amounts of B.sub.2O.sub.3, however, lead to
reductions in strain point (approximately 10.degree. C. for each
mole percent increase in B.sub.2O.sub.3 above 7.0 mole percent),
modulus, and chemical durability.
[0077] The glass substrate will preferably have a strain point
equal to or greater than 650.degree. C., equal to or greater than
655.degree. C., or equal to or greater than 660.degree. C.), a
Young's modulus equal to or greater than 10.0.times.10.sup.6 psi
(more preferably, and a chemical durability as described above in
connection with the discussion of the SiO.sub.2 content of the
glass. A high strain point is desirable to help prevent panel
distortion due to compaction/shrinkage during thermal processing
subsequent to manufacturing of the glass. A high Young's modulus is
desirable since it reduces the amount of sag exhibited by large
glass sheets during shipping and handling.
[0078] In addition to the glass formers (SiO.sub.2,
Al.sub.2O.sub.3, and B.sub.2O.sub.3), the glass substrate will
preferably also include at least two alkaline earth oxides, i.e.,
at least MgO and CaO, and, optionally, SrO and/or BaO. The alkaline
earth oxides provide the glass with various properties important to
melting, fining, forming, and ultimate use. In terms of
concentrations, MgO should be greater than or equal to 1.0 mole
percent in order to achieve the various benefits associated with
MgO described above. Preferably, the MgO concentration is between
1.6 and 2.4 mole percent. Of the alkaline earth oxides, the CaO
concentration in the glass substrate is the largest. CaO enables
producing low liquidus temperatures (high liquidus viscosities),
high strain points and moduli, and CTE's in the most desired ranges
for flat panel applications, specifically, AMLCD applications. It
also contributes favorably to chemical durability, and compared to
other alkaline earth oxides it is relatively inexpensive as a batch
material. Accordingly, the CaO concentration is preferably greater
than or equal to 6.0 mole percent. However, at high concentrations,
CaO increases density and CTE. Accordingly, the CaO concentration
of the glasses of the invention is preferably less than or equal to
11.5 mole percent, and more preferably, the CaO concentration is
between 6.5 and 10.5 mole percent.
[0079] The glass substrate described in the process can be what is
referred to in the art as laminated glass. In one aspect, glass
substrate is produced by fusion drawing to at least one exposed
surface of a glass core a glass skin. The glass skin will possess a
strain point greater than 650.degree. C. In other examples, the
skin glass composition can have a strain point greater than 670,
690, 710, 730, 750 770, or 790.degree. C. The strain point of the
disclosed compositions can be determined by one of ordinary skill
in the art using known techniques. For example, the strain point
can be determined using ASTM method C336.
[0080] In some examples, the glass skin can be applied to an
exposed surface of a glass core by a fusion process. An example of
a suitable fusion process is disclosed in U.S. Pat. No. 4,214,886,
which is incorporated by reference herein in its entirety. The
fusion glass substrate forming process can be summarized as
follows. At least two glasses of different compositions (e.g., the
base or core glass sheet and the skin) are separately melted. Each
of the glasses is then delivered through an appropriate delivery
system to an overflow distributor. The distributors are mounted one
above the other so that the glass from each flows over top edge
portions of the distributor and down at least one side to form a
uniform flow layer of appropriate thickness on one or both sides of
the distributor. The molten glass overflowing the lower distributor
flows downwardly along the distributor walls and forms an initial
glass flow layer adjacent to the converging outer surfaces of the
bottom distributor. Likewise, molten glass overflowing from the
upper distributor flows downwardly over the upper distributor walls
and flows over an outer surface of the initial glass flow layer.
The two individual layers of glass from each converging sidewall of
the two distributors are brought together and fused at the draw
line to form a single continuously laminated sheet. The central
glass in a two-glass laminate is called the core glass, whereas the
glasses flowing down the external surface of the core glass are
called skin glasses.
[0081] Conversely, when just one skin glass is fused directly to
the core, the skin is "adjacent" to the core.
[0082] The overflow distributor process provides a fire polished
surface to the sheet glass so formed, and the uniformly distributed
thickness of the glass provided by the controlled distributor,
provides a glass sheet with superior optical quality. The glass
substrates formed can have a thickness from 10 .mu.m to 5 mm. Other
fusion processes, which can be used in the methods disclosed
herein, are described in U.S. Pat. Nos. 3,338,696, 3,682,609,
4,102,664, 4,880,453, and U.S. Published Application No.
2005-0001201, which are incorporated by reference herein in their
entireties. The fusion manufacturing process developed by Corning
Incorporated offers critical advantages for the display industry,
including: one, glass that is flat with excellent thickness
control; and two, glass that has a pristine surface quality and
scalability. Substrate flatness is particularly critical in the
production of panels for liquid crystal display (LCD) televisions
as any deviations from flatness can result in distortions.
[0083] In another implementation of the described process, the
glass substrate will possess a strain point higher than 640.degree.
C., CTE in the range of 31-57.times.10.sup.-7/.degree. C., a weight
loss less than 20 mg/cm.sup.2 after immersion for 24 hours in an
aqueous 5% by weight HCl solution at 95.degree. C., that is
nominally free from alkali metal oxides and has a composition
consisting essentially, calculated in weight percent on the oxide
basis, of 49-67% SiO.sub.2, at least 6% Al.sub.2O.sub.3,
SiO.sub.2+Al.sub.2O.sub.3>68%, 0-15% B.sub.2O.sub.3, at least
one alkaline earth metal oxide selected from the group consisting
of, in the preparations indicated, 0-21% BaO, 0-15% SrO, 0-18% CaO,
0-8% MgO and 12-30% BaO+CaO+SrO+MgO.
[0084] Black Matrix Materials
[0085] Most types of black matrix materials can be used in the
described process, including either photosensitive or
non-photosensitive materials. Some of the more preferred types of
black matrix materials are polymers, and include epoxy, acrylic,
siloxane, and polyimide polymers. Acrylic and polyimide polymers
are known to behave more favorably in extended high temperature
environments, and generally have greater shelf stability, and thus,
can provide certain advantages over the other common black matrix
materials. In most instances, photosensitive acrylic polymers would
be favored over thermally sensitive acrylic polymers. In that case,
a photosensitive black matrix material will include an acrylic, a
photo-polymerizable monomer, and a photoinitiator. Nevertheless,
the choice of black matrix material will depend upon several
factors, including, but not limited to, the selection of adhesion
agent, the developing solutions and wash solutions used to etch the
black matrix, and the degree to which the adhesion agent interacts
with the black matrix material for a given glass substrate.
[0086] Some examples of acrylic include copolymers of a plurality
of acrylate(s) and/or methacrylate(s) selected from the group
consisting of hydrophobic alkyl acrylates and methacrylates such as
acrylic acid, methacrylic acid, methyl acrylate and methyl
methacrylate; cyclic acrylates and cyclic methacrylates; to
relatively more hydrophilic acrylates and methacrylates having a
functional group, such as hydroxyethyl acrylate and hydroxyethyl
methacrylate. The acrylic may be a copolymer having other
monomer(s) such as styrene, alpha-methylstyrene, acrylonitrile,
itaconic acid esters and fumaric acid esters. The acrylic polymer
will generally have a weight average molecular weight of about 1000
to 200,000.
[0087] The photo-polymerizable monomer can include a bifunctional
or multifunctional monomer. Some examples of the bifunctional
monomer include 1,6-hexanediol diacrylate, ethylene glycol
diacrylate, neopentyl glycol diacrylate and triethylene glycol
diacrylate, as well as acrylates containing (an) alicyclic
structure(s), such as dicyclopentane diene, and acrylates
containing (a) polycyclic aromatic ring(s) such as fluorene.
Examples of the multifunctional monomer include trimethylolpropane
triacrylate, pentaerythritol triacrylate, ditrimethylolpropane
tetracrylate, dipentaerythritol penta- and hexaacrylates.
[0088] To improve upon the solvent resistance and heat resistance,
the black matrix material can also include an epoxy compound or an
epoxy curing agent. The acrylic polymer itself may contain an epoxy
group. Some examples of the epoxy compound to be used include
bisphenol A type epoxy compounds, bisphenol F type epoxy compounds,
phenolic novolac epoxy compounds, cresol novolak epoxy compounds,
trishydroxyphenyl methane-type epoxy compounds, alicyclic epoxy
compounds, glycidyl ester-based epoxy compounds,
glycidylamine-based epoxy compounds, heterocyclic epoxy compounds
and fluorene-containing epoxy compounds.
[0089] It is also understood by those in the art, that there will
be an optimum height to the cured, patterned segments of black
matrix. The factors to be considered include the color filter
application (the type of flat panel display), and the stability of
the pattern over the processing conditions. In general, the height
of the black matrix layer is from 1.0 .mu.m to 4.0 .mu.m, or from
2.0 .mu.m to 3.0 .mu.m, the latter being particularly favored if
the color filter is formed using an ink jet system. When the height
of the black matrix layer exceeds 4.0 .mu.m, the strength and
pattern accuracy or resolution of the material is potentially
compromised. On the other hand, if the height of the black matrix
layer is less than 1.0 .mu.m an ink break can easily happen when
ink layer is deposited within the patterned matrix wells.
[0090] The following examples are put forth so as to provide those
of ordinary skill in the art with a complete disclosure and
description of how the articles and methods described and claimed
are made and evaluated, and are intended to be purely exemplary and
are not intended to limit the scope of what the inventors regard as
their invention. Efforts have been made to ensure accuracy with
respect to numbers (e.g., amounts, temperature, etc.) but some
errors and deviations should be accounted for. Unless indicated
otherwise, parts are parts by weight, temperature is in .degree.
C., or if not stated, the temperature at which the experiment or
measurement is conducted is about room temperature. Pressure is at
or near atmospheric unless stated otherwise. There are numerous
variations and combinations of reaction conditions, e.g., component
concentrations, desired solvents, solvent mixtures, temperatures,
pressures and other reaction ranges and conditions that can be used
to optimize the product purity and yield obtained from the
described process.
EXAMPLES
Example 1
Measurement of Water and Diiodomethane Contact Angles for a Glass
Substrate
[0091] Water contact angle measurements and diiodomethane contact
angle measurements are conducted using a Kruss DSA 3 instrument.
When the probe liquid is water, the Kruss DSA instrument dispenses
a 2 .mu.L drop of water on the surface of a glass substrate at a
rate of 100 .mu.L/min, captures an image, and determines the
contact angle of the water droplet against the glass surface using
the tangent or circle method. When the probe liquid is
diiodomethane, the Kruss DSA instrument dispenses 2 .mu.L volumes.
The final contact angle determined is based on the fit of the lines
determined by these methods with the actual physically determined
water contact angle.
[0092] In many instances, treating a glass substrate with the
adhesion agent will increase the water contact angle of the glass
substrate by at least two times relative to a well-cleaned,
non-treated, control glass substrate. Essentially, the application
of the adhesion agent will increase the hydrophobic character of a
surface of the glass substrate.
[0093] As water contact angles do not necessarily define coated
surfaces uniquely, other descriptors need to be made. This includes
not only the surface energy of the treated surface but how that
surface interacts with the black matrix material or developing
solutions. The probe liquids, water and diiodomethane have the
following surface tension properties. Water has a total surface
tension of 72.8 mN/m. The polar component is 46.4 mN/m and the
dispersive component is 26.4 mN/m. Diiodomethane has a total
surface tension of 50.8 mN/m with the dispersive component being
50.8 mN/m and the polar component being 0.0 mN/m.
[0094] The water contact angles for a glass substrate, Lotus.RTM.
XT from Corning Incorporated, and the glass substrate treated with
YSAM C18, were obtained and listed in Table I. One liter aqueous
solutions of YSAM C18 were prepared as follows. Deionized water,
990.16 mL, is added to a vessel, and with stirring (a magnetic stir
bar is sufficient) 0.48 mL of acetic acid followed by 9.36 mL of
YSAM C18 solution (60% YSAM C18, 40% methanol) is added, to make a
0.5 wt % YSAM C18 solution. The aqueous solution is stirred for a
total of about 30 minutes. The pH of the solution is about 3.5. The
glass substrate is dipped into the solution and maintained in
contact with the solution for 30 s at 25.degree. C. or room
temperature. The glass substrate is removed from the aqueous silane
solution, rinsed for 60 s with deionized water, and dried using a
clean, dry air/nitrogen flow.
[0095] The contact angles were determined using water and
diiodomethane as probe liquids. Ten sample drops of each liquid
were measured to determine each contact angle on the glass surface.
The control is a clean glass substrate with no surface treatment.
The sample and control glass substrates are prewashed with 4%
Semiclean KG detergent or air plasma cleaned prior to the
treatment. In the plasma cleaning process, substrates were placed
in the plasma chamber, air was pumped out to 100 mTorr followed by
air introduction at 1 cc/min, maintaining the 100 mTorr chamber
pressure, and the plasma was turned on for 15 s.
[0096] Using the average contact angle data reported in Table I,
the surface energies can be calculated for the glass surfaces and
are reported in Table V. The Reference Glass values in Table I are
for freshly cleaned "reference glasses".
TABLE-US-00002 TABLE I Water and DIM Contact Angles for Control and
YSAM C18 Treated Glass. Reference Reference Glass Treated Treated
Glass Glass Water Diiodomethane Glass Water Diiodomethane Contact
Contact Angle Contact Contact Angle Drop # Angle (.degree.)
(.degree.) Angle (.degree.) (.degree.) 1 3.8 39.7 70.9 47.3 2 3.5
39.2 73.1 48.8 3 3.5 39.8 72.2 48.3 4 3.9 39.6 75.1 48.7 5 3.9 38.9
69.4 48.6 6 4.1 38.5 69.9 48.8 7 3.7 37.9 69.2 48.1 8 3.8 38.4 72.9
50.7 9 4.1 39.1 69.6 47.2 10 3.9 39.4 70.9 39.2 11 4.1 38.9 72.1
48.8 12 3.9 37.6 78.1 49.7 Average 3.9 38.9 72.0 47.9 Std. Dev. 0.2
0.7 2.6 2.9
Example 2
Measurement of Liquid Surface Tensions for Developer Solutions
[0097] The surface tension of four developing solutions were
determined using a combination of the described contact angle
measurements on poly(tertafluoroethylene) (PTFE) and Wilhelmy plate
method. This was done as a means of separating each overall surface
tension into polar and dispersive components. According to the
Fowkes surface energy theory (based on the geometric mean), the
dispersive component of a liquid can be determined by knowing its
overall surface tension and its contact angle against PTFE (assumed
to have a total surface energy of 18 mN/m and no polar component).
The lower the contact angle for the liquid on PTFE, the higher the
non-polar (dispersive) component of its surface because a non-polar
surface will preferentially wet with a non-polar liquid.
[0098] The equation used is as follows:
.gamma. l d = .gamma. l 2 ( cos .theta. PTFE + 1 ) 2 72
##EQU00005##
wherein .theta..sub.PTFE=the contact angle measured between PTFE
and the probe liquid, and the dispersive surface tension component
(.gamma..sub.l.sup.d) can be determined for any liquid for which
the overall surface tension (.gamma..sub.l) is known, simply by
measuring the contact angle between that liquid and PTFE
(.theta..sub.PTFE), and using the equation above. The polar surface
tension component for the liquid is then determined by difference:
(.gamma..sub.l.sup.p=.gamma..sub.l-.gamma..sub.l.sup.d). A surface
polarity can be expressed as a percentage as
(%=.gamma..sub.l.sup.p.times.100/.gamma..sub.l).
[0099] The following contact angle data were collected by placing 5
droplets of each liquid onto PTFE using a Kruss Drop Shape Analysis
System DSA10. The contact angles are listed in Table II.
TABLE-US-00003 TABLE II Developer Solution Contact Angles Measured
on PTFE. 1.0% KOH 0.24% KOH PTFE PTFE 1.0% Na.sub.2CO.sub.3 0.24%
Na.sub.2CO.sub.3 Contact Contact PTFE Contact PTFE Contact Test #
Angle (.degree.) Angle (.degree.) Angle (.degree.) Angle (.degree.)
1 114.9 113.8 114.8 114.0 2 114.8 114.1 114.7 113.7 3 115.1 114.1
114.5 114.0 4 115.1 113.8 114.6 113.8 5 115.2 114.2 114.9 114.0
Average 115.0 114.0 114.7 113.9 Std. Dev. 0.2 0.2 0.2 0.1
[0100] All of the salt/base solutions have surface tensions and
surface polarities which are slightly higher than pure water. This
is a common effect of adding ions to water which enhances hydrogen
bonding effects in the water. As expected, the surface tensions are
higher at 1.0% than at 0.24% with the same salt due to the added
salt concentration. The salt solutions will possess relatively low
interfacial tensions on a polar (more hydrophilic) surface of a
control glass substrate and high interfacial tensions with a less
polar (more hydrophobic) surface of a glass substrate treated with
an adhesion agent. In regard to the latter, the salt solutions will
be more incompatible in terms of surface tension and surface
polarity. In contrast, the black matrix material has a low surface
polarity and so will be more compatible with the low polarity
treated glass surface and less compatible with a more polar
untreated (control) glass surface.
[0101] The objective, to achieve low interfacial tension and
thereby more favorable adhesion, depends on both overall surface
energy as well as the surface polarity of the substrate matching
the surface polarity of the black matrix material. Using the
contact angle data of Table II and the Fowkes model equation above,
one can calculate the surface tensions for the listed salt
(developing) solutions as well as the interfacial tension between
these solutions and the glass substrate.
TABLE-US-00004 TABLE III Surface Tension for Developing Solutions.
Interfacial Tension Overall with Interfacial Surface Polar
Dispersive Control Tension with Developer Tension Comp. Comp. Glass
Coated Glass Solution (mN/m) (mN/m) (mN/m) (mN/m) (mN/m) 1.0% KOH
73.17 48.38 24.79 2.79 27.07 0.24% KOH 72.90 46.92 25.98 2.30 25.85
1.0% Na.sub.2CO.sub.3 73.07 47.94 25.13 2.64 26.70 0.24%
Na.sub.2CO.sub.3 72.88 46.72 26.16 2.25 25.73
[0102] In accordance with the described method of treating a glass
substrate with an adhesion agent, it remains of particular interest
for the adhesion agent to increase the interfacial tension between
a developing solution and the treated substrate by at least five
times, e.g., by at least six times, by at least seven times, or by
at least eight times, relative to a non-treated, control glass
substrate.
[0103] In addition, it is also of interest for the adhesion agent
to decrease the interfacial tension between black matrix and the
treated substrate by at least three times, e.g., by at five times,
by at least seven times, or by at least ten times, relative to a
non-treated, control glass substrate.
Example 3
Measurement of Delamination Time for Black Matrix Segment
[0104] As demonstrated in FIG. 1, a LOTUS.RTM. glass substrate was
treated with various adhesion agents, including Virtubond (shown in
FIG. 1 as "A"), YSAM C18 (shown in FIG. 1 as "B"), and HMDS (shown
in FIG. 1 as "C"). Some of the applied adhesion agents following a
60 second water rinse significantly increased the hydrophobic
character of the glass surface as indicated by water contact angles
of about 70.degree. or more. Other applied adhesion agents
following the same rinse step (shown collectively in FIG. 1 as "0")
had significantly less effect on the hydrophobic character of the
glass surface.
[0105] A variety of methods were utilized to deposit the adhesive
agent on the surface of the glass substrate. For
hexamethyldisilazane, the disilazane was placed into a petri dish
and placed inside a vacuum desiccator. A small glass substrate was
elevated above the petri dish. The desiccator was then closed and
vacuum pulled for 1 minute, and the substrate sat in a static
vacuum for one min. The desiccator was then purged with nitrogen or
clean air, the treated glass was then removed and placed onto a hot
plate at 140.degree. C. for 3 min to evolve ammonia and strongly
bond HMDS to the glass surface. For the alkyl silanes, aqueous
solutions were prepared in accordance with Example 1, and the glass
substrates were dipped, rinsed and dried as described. For the
epoxy silanes, aqueous solutions were prepared in approximately one
liter of deionized water and 0.01 mL of 99% glacial acetic acid was
added to make pH.about.5 solution.
3-glycidoxypropyltrimethoxysilane (9.34 mL) was added to make an
approximate 1 wt % solution. The mixture was then stirred for 2 h
to allow hydrolysis to occur. The glass substrates were dipped,
rinsed and dried as already described. For epoxy silanes deposited
out of 50/50 ethanol/water, 0.5 ml of 99% glacial acetic acid per 1
L of water was mixed to make a pH.about.4 solution. In the instance
where water/ethanol mixtures were used the appropriate volumes of
each solvent were used to make the stated solutions. Again, the
glass substrates were then dipped, rinsed and dried as described.
For octadecylammonium chloride, 1 g of the alkyl salt was added to
1000 mL of deionized water until dissolved. Again, the glass
substrates were dipped, rinsed and dried as described. Octadecanol
was evaporated directly from a dish of the molten material (mp 60
degrees C.) onto sample pieces of room temperature glass held above
the surface. The glass substrate was typically on the order of a
few mm from the dish top edge and 3.5 cm from the surface of the
octadecanol. Deposition took place at 90 degrees C. melt
temperature for 10 s. Samples of individual liquid silanes (as
supplied by Gelest) were transferred to a small petri dish and
placed in the bottom of a vacuum desiccator. Sufficient liquid was
used, such that there would still be liquid remaining at the end of
the treatment cycle (max loss observed was .about.1 mL/h). The
desiccator shelf was then inserted and clean glass samples were
arrayed in a rack on that shelf. The desiccator lid was attached
and connected to a Gast.TM. Oil-Less Diaphragm-Type Pressure/Vacuum
Pump (DOAP704AA) and vacuum applied (gauge read approx. 23 in Hg)
and maintained for 6 h. After vapor deposition, the vacuum was
released and the samples transferred to a pre-heated oven
(100.degree. C.) for 10 min. Samples were then cooled and
immediately used for analysis or black matrix processing. Silanes
deposited by this method were 3-acryloxypropyltrimethoxysilane
(Gelest: SIA0200.0) and ethyltrimethoxysilane (Gelest:
SIE49010.4).
[0106] Following the treating of the glass substrates, black matrix
was deposited as follows. The black matrix (Tokyo Ohka Product #
CFPR BK-5100NR) was removed from refrigerated storage and allowed
to acclimate to room temperature. The black matrix material was
spin coated onto the substrates at 1000 rpm for 5 seconds using an
initial dose of 8 mL of black matrix for a 5 inch by 5 inch
substrate. Following spin deposition, the sample substrate is
allowed to solvent evaporate in air for about 2 minutes. Then the
sample is heated at 70.degree. C. for 125 s to allow further
evaporation of the solvents from the black matrix liquid material.
The pattern mask is applied to the substrate, the sample is then UV
exposed (I line) at a line width of 5 .mu.m for 1.5 s and the
pattern mask removed. The sample is then developed with 500 mL of
developing solution (KOH, Na.sub.2CO.sub.3 or DCD developer) for
various times followed by a deionized water rinse in 750 mL for 1
min followed by second a water rinse in 750 mL for 35 s. The
samples are then placed on an oven rack and heated for 30 min at
230.degree. C. The amount of time required in the developer
solution for delamination of the 5 .mu.m black matrix lines from
the treated substrates was measured and compared to the amount of
time required for delamination of the 5 .mu.m black matrix lines
from the untreated control substrates and reported as the
difference between these delamination times in Table IV and FIG. 1.
Visual examination of delamination is done by inspecting using
transmission or reflecting mode on an optical microscope using
magnification of up to 100.times..
TABLE-US-00005 TABLE IV Delamination Time Shift and Water Contact
Angle for a Variety of Chemistries 5 .mu.m line Water Development
Contact Time Shift from Surface Treatment/Condition Angle Control
(s) SC-1 1:2:80 3.1 5.00 Octadecanol 19.5 20.00
(3-Acryloxypropyl)trimethoxysilane 27.3 20.00
(3-Glycidoxypropyl)trimethoxysilane 13.7 15.00 Parker 488A 3.8
-15.00 4% KOH solution with alkaline detergent 2.0 -10.00 Semiclean
KG 2.8 0.00 SC-1 1:1:5 2.8 -5.00 SC-1 1:2:80 2.6 5.00 1:200 HCl 2.9
-15.00 SC-1 1:2:80 3.4 10.00 Plasma O2, Argon 3.1 0.00 HMDS 74.5
125.00 Virtubond .TM. 70.0 55.00 0.5 wt. % YSAM 70.7 90.00
Example 4
Cleaning Glass Substrates Following Treatment with Adhesion
Agent
[0107] To accommodate thinner and thinner segments of patterned
black matrix, glass cleanliness becomes more important, and the
design specifications, e.g., a maximum particle density, for color
filter and TFT grade glass substrates continue to decrease.
Essentially, the glass substrate must be substantially free of
loose environmental particles. Cleaning methods may include
mechanical means such as physical brush washing, ultrasonics,
bubble jet, high pressure spray for large (>1 .mu.m particles),
or megasonics for submicron particles, as well as chemical means
such as detergent, alkali, hot water, steam, etc. for the removal
of not only particulate but also organic and/or metallic ion
contaminants. Moreover, the sequence of cleaning steps may also be
critical. For example, the removal of larger size particulate prior
to the removal of smaller size particulate may prove
beneficial.
[0108] The treatment of a clean glass substrate with an
organic-based adhesion agent to enhance black matrix adhesion to
the substrate as described herein may be required to survive one or
more wash steps so that unwanted organics or particulates may be
removed while the adhesive agent is retained. Hence it becomes
important to assess the ability of a treated surface to withstand a
wash process and retain its objective properties, to provide
enhanced black matrix adhesion.
[0109] The adhesion agent, YSAM C18, was applied to a LOTUS.RTM.
glass substrate as described in Example 1 and four different
cleaning or wash steps were used to remove excess agent and
unwanted particles and organics from the treated substrate. The
black matrix ink was deposited and patterned as described in
Example 3 except 2 inch.times.2 inch glass substrates were used.
The time versus contact angle data of FIG. 2 represents how well
the YSAM C18 agent is maintained on the glass surface following
several types of wash or clean steps including air plasma (shown in
FIG. 2 as "E"), an aqueous 0.24% KOH solution (shown in FIG. 2 as
"F"), an aqueous 4% KOH solution with an alkaline detergent
(hereafter, "4% KOH SP") (shown in FIG. 2 as "G"), and water (shown
in FIG. 2 as "H").
[0110] Again, the developing process included a dipping process in
about 500 mL of solution with no physical action. For example, the
KOH development was conducted at room temperature. For water wash,
the liquid was likewise at room temperature but washing took place
under flow of 1 L/min. For detergent wash, 4% KOH SP at 65.degree.
C. was used without ultrasonic agitation and without flow. In the
plasma cleaning process, substrates were placed in the plasma
chamber, air was pumped out to 100 mTorr followed by air
introduction at 1 cc/min, maintaining the 100 mTorr chamber
pressure, and the plasma was turned on for 15 s.
[0111] The effect of a water wash at 15 and 30 seconds was not
measured since there was little or no change after 60 or 300
seconds and is therefore not shown in FIG. 2. The x-axis shows the
length of time each wash or clean solution is in contact with the
treated substrate. It is readily seen that YSAM C18 is maintained
to a greater extent on the substrate surface following a water wash
or a basic KOH wash, than if an air plasma or detergent wash is
used.
Example 5
Cleaning Glass Substrates Following Treatment with Alkyl Ammonium
Salt Adhesion Agents
[0112] The adhesion agents, octadecyl (C18) trimethyl ammonium
chloride (shown in FIG. 3 as "M"), hexadecyl (C16) trimethyl
ammonium bromide (shown in FIG. 3 as "L"), dodecyltrimethyl (C12)
ammonium bromide (shown in FIG. 3 as "K"), and hexyltrimethyl (C6)
ammonium bromide (shown in FIG. 3 as "J") were separately applied
to a LOTUS.RTM. glass substrates as described in Example 3, as
compared to a substrate that was plasma cleaned only (shown in FIG.
3 as "I"). For each applied adhesion agent three different wash
cycles were used to determine the extent to which each agent is
maintained on the substrate surface for each wash cycle. Wash Cycle
1: a 0.1% KOH solution is applied for one minute (shown as "1" in
FIG. 3). Wash Cycle 2: wash cycle 1 plus a water rinse for one
minute (shown as "2" in FIG. 3). Wash Cycle 3: wash cycle 1 plus 4%
KOH SP at 65.degree. C. for one minute, followed by a one minute
water rinse (shown as "3" in FIG. 3).
[0113] FIG. 3 provides a very strong indication that the lower
alkyl chain ammonium salts, i.e., the C6 and C12 ammonium alkyls,
are not maintained on the glass surface--the C6 alkyl exhibiting
poor survivability even in the one minute water wash. In contrast,
the C16 and C18 ammonium alkyls exhibit acceptable maintenance
performance for all three wash cycles.
Example 6
Comparing Delamination Times of Treated Surfaces in Developer
Solutions
[0114] Time delamination measurements for 5 .mu.m black matrix
segments on LOTUS.RTM. glass substrates were conducted using two
different adhesion agents, YSAM C18 and octadecyl (C18) trimethyl
ammonium chloride (OC18 TMAC), with two different developing
solutions, 0.24 wt % KOH and 1 wt % sodium carbonate
(Na.sub.2CO.sub.3) in contact with the substrate (with OC18
TMAC+KOH shown in FIG. 4 as "N1", OC18 TMAC+Na.sub.2CO.sub.3 shown
in FIG. 4 as "N2", YSAM C18+KOH shown in FIG. 4 as "N3", and YSAM
C18+Na.sub.2CO.sub.3 shown in FIG. 4 as "N4"). As shown in FIG. 4,
the C18 alkyl ammonium chloride exhibits some black matrix adhesion
benefit by extending delamination times in both developer solutions
by about 4 to 5 seconds longer than the untreated control
substrate. In contrast, YSAM C18 exhibits much longer delamination
times in each developing solution, e.g., extending the delamination
time by about 50 seconds in the carbonate development solution
relative to an untreated control substrate. As shown in FIG. 4, two
types of photo masks were used to determine the extension of
development time. One photo mask had lines with anchors (shown as
"PM1" in FIG. 4) to simulate wells in which an RGB ink could be
placed. The other photo mask (shown as "PM2" in FIG. 4) had only
lines without anchors to determine the extension of development
time.
[0115] Accordingly, it is of particular interest for an adhesion
agent to provide an article with an increase in delamination time
of at least 5 seconds of a test segment with a line width of 5
.mu.m. The delamination time is determined relative to a control
article, as described above following contact with a 0.24 wt %
potassium hydroxide (KOH) solution. It is to be well understood by
a person of skill in the art that a control article is an article
that is prepared in the same manner as a test article with the
exception that an adhesion agent is not positioned between the
glass substrate and the black matrix segment. It is also of
particular interest, that an adhesion agent also provides an
article with an increase in delamination time of at least 5 seconds
of a test segment with a line width of 5 .mu.m following contact
with a 1.0 wt % sodium carbonate solution for one minute relative
to a control article.
Example 7
Correlation Between Overall Surface Energy and Line
Survivability
[0116] Overall surface energies of some exemplary glass substrate
surface treatments were calculated using the Wu model, as described
above, and compared to 4 .mu.m line survivability of the surface
treatment at 150 seconds. The results are set forth in Table V.
TABLE-US-00006 TABLE V Surface Characteristics of Glass Substrate
Surface Treatments Overall Polar Dispersive 4 .mu.m Line Surface
Surface Compo- Compo- Surface Survivability Treatment on Energy
nent nent Polarity at 150 s LOTUS .RTM. Glass (mN/m) (mN/m) (mN/m)
(%) (%) Control 79.9 39.2 40.7 49.1 0 YSAM C18 49.2 12.7 36.5 25.9
86.9 ethyltrimethoxy- 61.1 25.5 35.6 41.8 53.7 silane
acryloxypropyl 54.5 18.5 36.0 33.9 61.5 trimethoxy silane
[0117] From the surface energy data of Table V one notices that in
general, surfaces that reduce the overall surface energy below
approximately 65 mN/m or 65 mJ/m.sup.2 are of particular interest.
In addition, one also notices a significant change in the polar
component of the surface energy for each of the treated glass
substrates. The agents, which we refer to as YSAM C18 and YSAM C14
(see below), have at least a 50% reduction in the polar component.
In fact, YSAM C18 exhibits about a 90% reduction in the polar
component, and about a 50% reduction in the overall surface energy
relative to the control substrate. In accordance with these
measurements, an adhesion agent that can reduce the polar component
of surface energy of a treated glass substrate by at least 30%, at
least 40%, by at least 50%, by at least 65%, or by at least 80%,
relative to a non-treated, control glass substrate is of particular
interest. In addition, from the measurement of water and DIM
contact angles one can define a term "surface polarity". The
surface polarity is a percent ratio defined as the {[calculated
polar component]/[overall surface energy]}.times.100. The surface
polarity is a ratio that is associated with the polar character of
a surface of a glass substrate. As indicated in Table V, the
control substrate having a more hydrophilic surface is expected to
have a relatively high surface polarity. In contrast, the substrate
treated with an adhesion agent is expected to have a lower surface
polarity. In accordance with calculated surface polarity, an
adhesion agent that provides a surface polarity of 35% or less is
of interest, e.g., a surface polarity of from 5% to 35%. Of greater
interest, is for an adhesion agent to provide a surface polarity of
30% or less, of 20% or less, of 15% or less, or of 10% or less. An
adhesion agent that provides a surface polarity in the range of 10%
to 25% is of particular interest. Again, values of surface polarity
are obtained by measurement of water and DIM contact angles--a
method of measurement well known to persons of skill in the art of
characterizing surface properties of any substrate or film. The
data was extracted using the Wu model.
[0118] Adhesion of black matrix to the glass surface correlates to
the surface energy of the treated glass substrate. Dispersive,
polar and total surface energy (mN/m) were determined for a series
of surfaces using two fluid contact angle measurements with
H.sub.2O and DIM. Surface energy values are based on calculations
from the Wu Model. It is understood that the use of other models
(such as geometric mean) will result in different absolute values
but exhibit the same trend. In Table IV, HDMS, octadecanol,
acryloxypropyl TMS, and ethyltrimethyoxysilane were applied in
accordance with the vapor deposition methods described above.
Rain-X and YSAM were applied in accordance with solution deposition
methods as described above. CH.sub.4 plasma was applied in
accordance with plasma deposition methods as described above,
wherein four passes of atmospheric plasma (AP) were made using a
plasma jet.
TABLE-US-00007 TABLE VI Calculated Wu Model Surface Energies and
Line Survivability of Surfaces 4 .mu.m Line Survivability Surface D
(mN/m) P (mN/m) T (mN/m) at 150 s (%) 10% Rain-X 31.9 4.8 36.7 0.0
HMDS 29.4 11.6 40.9 83.9 CH.sub.4 Plasma 42.8 2.9 45.7 76.9 0.1%
YSAM 36.2 10.9 47.2 86.9 acryloxypropyl TMS 36.0 18.5 54.5 61.5
Octadecanol 37.0 21.6 58.6 0.0 ethyltrimethoxysilane 35.6 25.5 61.1
53.7 Control Lotus XT 40.5 39.3 79.8 0.0
[0119] FIG. 5 shows correlation between total surface energy for
covalently bonded adhesion agents and the resulting 4 .mu.m
unanchored line survivability at 150 s in DCD developer. FIG. 5
also shows data for select treatments with line survivability of 0%
which is attributed to the lack of covalent bonding between the
adhesion promoter and the glass in those cases.
[0120] In addition, the above surface energy measurements
demonstrate that an adhesion agent that can reduce the overall
surface energy of a treated glass substrate by at least 15%, by at
least 25%, or by at least 40%, relative to a non-treated, control
glass substrate is of particular interest. Ideally, one would like
to observe a decrease in the polar component as well as a decrease
in the overall surface tension of a treated glass substrate,
particularly, in the instance where the black matrix material has a
hydrophobic character as described above and utilized in the
process.
Example 8
Correlation Between Overall Surface Energy and Delamination
Time
[0121] Overall surface energies and delamination times were
calculated as described above and compared for exemplary surface
treatments as set forth in Table VII below.
[0122] As one can see from the surface energy data of Table VII,
there is little or no difference in the polar component and the
overall surface tension for the control glass substrate, LOTUS.RTM.
by Corning, and the glass substrate treated with an epoxy silane or
YSAM C1. The data of Table VII is consistent with the data of FIG.
1, which demonstrates that YSAM C1 has little effect on increasing
the water contact angle of the glass substrate, and consequently,
has little or no effect on improving delamination times. One could
find it advantageous, however, to utilize such adhesion agents with
black matrix ink compositions having greater hydrophilic character
or reactive functionality, particular for the epoxy silane.
TABLE-US-00008 TABLE VII Surface Characteristics of Glass Substrate
with Surface Treatments Overall Polar Dispersive Surface Compo-
Compo- Surface 5 .mu.m line Lotus .RTM. with Energy nent nent
Polarity Delamination Silane Agent (mN/m) (mN/m) (mN/m) (%) time
(s) Control 79.9 39.2 40.7 49.1 t.sub.0 Epoxy Silane 71.6 31.0 40.6
43.0 t.sub.0 + 23.6 (95/5 EtOH/Water) Epoxy Silane 70.8 29.7 41.0
42.0 t.sub.0 + 21.6 (50/50 (EtOH/Water) Epoxy Silane 70.8 29.5 41.3
41.6 t.sub.0 + 11.5 (Water) YSAM C1 76.7 35.0 41.6 45.7 t.sub.0 +
0
Example 9
Work of Adhesion for Different Developer Solutions
[0123] Table VIII lists the calculated work of adhesion of black
matrix to the glass substrate in a developer solution (W.sub.l12),
and the corresponding f factor in the presence of three different
developing solutions using LOTUS.RTM. glass available from Corning
Incorporated.
[0124] Surfaces of a LOTUS.RTM. glass substrate were treated with
YSAM C18 in accordance with the method described in Example 1,
followed by the deposition of black matrix product # CFPR BK-5100NR
available from Tokyo Ohka Kogyo Co., Ltd using a spin-coating
process. The black matrix was then exposed to developer solution:
either 0.24 wt % aqueous potassium hydroxide, 1 wt % aqueous sodium
carbonate, or DCD-260CF (DCD), which is a 0.04 wt % KOH solution in
water that also includes a proprietary surfactant and is available
as a concentrate at 4 wt % KOH from Dongin Semichem Co. Ltd. The
delamination times were determined by the method described in
Example 3.
TABLE-US-00009 TABLE VIII Calculated Work of Adhesion for Different
Development Solutions Work of Developer adhesion, W.sub.112
Substrate Solution (mN/m) Factor f Control Lotus Glass 0.24 wt %
11.03 0.15 KOH 0.5 wt % YSAM C18 0.24 wt % 46.22 0.76 coated Lotus
Glass KOH Control Lotus Glass 1.0 wt % 12.02 0.16 Na.sub.2CO.sub.3
0.5 wt % YSAM C18 1.0 wt % 47.01 0.78 coated Lotus Glass
Na.sub.2CO.sub.3 Control Lotus Glass DCD 0.58 0.008 0.5 wt % YSAM
C18 DCD 2.97 0.05 coated Lotus Glass
[0125] Embodiments disclosed herein can provide for articles and
methods wherein an adhesion agent positioned between a glass
substrate and black matrix segments provides a total surface energy
of the glass substrate of 65 mN/m or less, such as 60 mN/m or less,
and further such as 55 mN/m or less, and yet further such as 50
mN/m or less, including from 35 mN/m to 65 mN/m, and further
including from 40 mN/m to 60 mN/m as determined by water and
diiodomethane contact angle measurements and application of the Wu
model as described herein.
[0126] Embodiments disclosed herein can provide for articles and
methods wherein an adhesion agent positioned between a glass
substrate and black matrix segments provides at least a 30%
reduction in surface polarity, such as at least a 35% reduction in
surface polarity, and further such as at least a 40% reduction in
surface polarity, and yet further such as at least a 50% reduction
in surface polarity, compared to a control untreated glass surface,
as determined by water and diiodomethane contact angle
measurements. For example, the adhesion agent may provide at least
a 30% reduction in the polar component of the overall surface
tension of the glass substrate, such as at least a 35% reduction in
the polar component of the overall surface tension of the glass
substrate relative to a non-treated control substrate.
[0127] Embodiments disclosed herein may also exhibit an increase in
delamination time of at least 5 seconds, such as at least 10
seconds, and further such as at least 20 seconds, of a test segment
with a line width of 5 .mu.m following contact with a 0.24 wt %
aqueous potassium hydroxide solution, relative to a control
article.
[0128] Embodiments disclosed herein may also exhibit an increase in
delamination time of at least 5 seconds, such as at least 10
seconds, and further such as at least 20 seconds, of a test segment
with a line width of 5 .mu.m following contact with a 1.0 wt %
aqueous sodium carbonate solution, relative to a control
article.
[0129] Embodiments disclosed herein may also include those in which
treating the surface of the glass substrate with the adhesion agent
increases the water contact angle of the glass substrate by at
least two times, such as at least three times, and further such as
at least four times, such as from two to ten times, relative to the
non-treated, control glass substrate.
[0130] Embodiments disclosed herein may also include treating a
surface of the glass substrate with an adhesion agent, wherein the
adhesion agent will increase the water contact angle of the glass
surface to at least 40.degree., such as at least 45.degree. and
further such as at least 50.degree., including from 40.degree. to
90.degree..
[0131] Embodiments disclosed herein may also include those in which
treating the glass substrate with the adhesion agent increases the
interfacial tension between a developing solution and the treated
glass substrate by at least five times, such as at least ten times,
relative to a non-treated, control glass substrate.
[0132] Embodiments disclosed herein may also include those in
which, after treating the surface of the glass substrate with the
adhesion agent and immediately prior to applying the black matrix
material to the surface of the glass substrate that is treated with
the adhesion agent, the adhesion agent remains on the glass surface
in sufficient quantity to provide at least one of: a total surface
energy of the glass substrate of 65 mN/m or less, and at least a
30% reduction in surface polarity compared to a control untreated
glass surface. Such embodiments may, for example, include those in
which a cleaning procedure is applied to the glass substrate
subsequent to treating the surface of the glass substrate with the
adhesion agent and prior to applying the black matrix material to
the surface of the glass substrate that is treated with the
adhesion agent.
[0133] It will be apparent to those skilled in the art that various
modifications and variations can be made without departing from the
spirit and scope of the claims.
* * * * *